Fuel shortage detection system for engine driven generator

Abstract

A system is provided for generating an alarm when the fuel surface level of an engine driven generator becomes smaller than a predetermined value, and stopping the engine after a predetermined time lapse from generating the alarm. Fuel shortage is detected by a fuel caution unit to cause an alarm unit to operate and further cause an engine stop unit to operate. The fuel caution unit causes the engine stop unit to stop after a short time lapse if the engine is restarted after the detection of fuel shortage. The system further includes an oil caution unit, overload caution unit, battery caution unit and power monitor accessories unit.

What is claimed is: 
     
       1. A fuel shortage detection system for an engine driven generator comprising: means for detecting a fuel shortage condition depending on measuring of the level of fuel in a fuel tank and for producing a level signal;   alarm means responsive to said signal from said detection means for generating an alarm;   timer means for providing time lapse signal when said signal from said detection means lasts for a predetermined time;   restart detection means for detecting that said engine is caused to restart and for providing a restart signal;   output means responsive to said signal from said restart means for outputting a signal after a time lapse shorter than said predetermined time lapse; and   engine stop means responsive to said signal from said timer means and said output means for stopping said engine.   
     
     
       2. A fuel shortage detection system for an engine driven generator according to claim 1, further comprising: current detection means for detecting a value of a load current of said generator; and   overload detection means for detecting an overload condition based on that the detected current value by said current detection means is larger than a predetermined value;   wherein the detected signal by said overload detection means is supplied to said alarm means.   
     
     
       3. A fuel shortage detection system for an engine driven generator according to claim 2, further comprising: display means for displaying the magnitude of the detected current value by said current detection means, by changing the number of a plurality of display elements to be turned on.   
     
     
       4. A fuel shortage detection system for an engine driven generator according to claim 3, wherein said current detection means comprises:   first current detection means for detecting an output current of a main winding of said generator; and   second current detection means for detecting a value corresponding to an overload condition of said generator based on a current of an excitation winding of said generator; and   said display means is adapted to change the number of a plurality of display elements to be turned on in accordance with the detected signal by said first current detection means, and in response to an output from said second current detection, adapted to turn on said display elements corresponding in number to said value corresponding to said overload condition.   
     
     
       5. A fuel shortage detection system for an engine driven generator according to claim 3, wherein said display means comprises in addition to said plurality of display elements, an auxiliary display element group disposed in an array for recognizing the display level of said plurality of display elements. 
     
     
       6. A fuel shortage detection system for an engine driven generator according to claim 1, further comprising: oil pressure lowering detection means for measuring an oil pressure of said engine and detecting that said measured oil pressure becomes lower than a predetermined value, wherein the detected signal by said oil pressure lowering detection means is supplied to said alarm means and said engine stop means.   
     
     
       7. A fuel shortage detection system for an engine driven generator according to claim 1, further comprising: a battery for supplying a power to said fuel shortage detection system; and   battery detection means for detecting that the surface level and specific gravity of electrolyte of said battery become smaller than predetermined values, the output from said battery detection means being adapted to be supplied to said alarm means.